The invention relates to a system for offshore cryogenic loading, especially for transfer of liquefied natural gas between two vessels.
Offshore production and loading of liquefied natural gas (LNG) for many years has been evaluated by several oil companies without developing to a reality. The most important obstacles for this are that
oil and gas fields hitherto have been developed in an economic manner by means of pipelines from the gas field to the LNG plant, and transport by means of LNG shuttle tankers to the market, and that
the technology for offshore production and loading has not been considered to be mature for such operations.
As the search for oil and gas is extended to more remote regions and deeper waters, new techniques and less costly solutions for oil and gas production are required. As a result, the technology for offshore LNG production and equipment for offshore LNG transfer are in the process of being developed, and several concepts have append If the remaining technology gap can be closed and an economic incentive is sufficiently big, one or more of these techniques may be put into use in the near figure.
Thus, the object of the invention is to provide a system for LNG transfer between two floating vessels, wherein the system is constructed for safe remote operation, and for stable and safe transfer with a high capacity.
For achieving the above-mentioned object there is provided such a system which, according to the invention is characterised in that it comprises a coupling head mounted at one end of a flexible pipe means and arranged for attachment on a platform at one end of one vessel when it is not in use, and a connection unit mounted at one end of the other vessel and comprising a pull-in funnel shaped for guided pull-in of the coupling head to a locking position in which the pipe means can be connected to transfer pipes on the vessel via a valve means arranged in the coupling head, the coupling head further being provided with a guide means and being connected to least one pull-in wire for guided pull-in of the coupling head into the connection unit by a winch means on the other vessel.
In an advantageous embodiment of the system the flexible pipe means consists of at least two parallel extending flexible pipes which are coupled to a respective valve in the valve means of the coupling head. Each valve preferably is bipartite to allow an emergency disconnection of the pipe means, and there is then also provided a cutter means for cutting of each pull-in wire in an emergency disconnection.